Is it permissible to recite adhkar through loudspeakers after the Friday prayer?

Reciting dhikr aloud with loudspeakers after the Friday prayer or any other prayers, on a continuous basis, is an innovation (bid‘ah). This is because it has not been authentically reported from the Prophet, peace and blessings be upon him, and because the default for dhikr is to lower the voice, as this is more conducive to reverence and veneration. The Prophet, peace and blessings be upon him, said: "O people, be easy on yourselves, for you are not calling upon one who is deaf or absent. You are calling upon One Who is All-Hearing, Ever-Near, and He is with you." An exception is made for what has been explicitly stated in the texts to be recited aloud, such as the talbiyah in Hajj and 'Umrah.